The World Health Organization on Friday denied Israel's charges it had colluded with Hamas by ignoring Israeli evidence of the group's "military use" of hospitals in the Gaza Strip.

WHO chief Tedros Adhanom Ghebreyesus also said that such accusations could endanger the UN health agency's staff on the ground.

He was responding to claims made Thursday by Israeli ambassador Meirav Eilon Shahar at a meeting of the WHO's board.

"WHO refutes Israel's accusation at the executive board meeting yesterday that WHO is in 'collusion' with Hamas and is 'turning a blind eye' to the suffering of hostages being held in Gaza," Tedros said on X.

"Such false claims are harmful and can endanger our staff who are risking their lives to serve the vulnerable."

He insisted that "WHO is impartial and is working for the health and well-being of all people".

Israel charges that Hamas is embedding itself in hospitals in the Gaza Strip and has been using civilians as human shields in the Palestinian territory.

In "every single hospital that the IDF searched in Gaza, it found evidence of Hamas' military use," Eilon Shahar said Thursday.

"These are undeniable facts that WHO chooses to ignore time and time again. This is not incompetence; it is collusion."

And following Tedros's comment, she doubled down.

"There is clear evidence of the use of hospitals by Hamas," Eilon Shahar wrote on X Friday evening.

There was also evidence, she said, of "the fact that hostages were taken to medical institutions after the brutal massacre of October 7th".

"This includes first hand accounts and CCTV footage. These are not 'false claims'. They are facts. Yet you have said nothing."

The Israeli ambassador warned WHO that "by not condemning Hamas or taking any action to prevent them embedding themselves in hospitals and civilian areas, you are putting those who you are supposed to protect in harms way".

"They deserve better."

Situation 'beyond words'

War erupted on October 7 when Hamas and other militants from Gaza launched unprecedented attacks on Israel which claimed about 1,140 lives, according to an AFP tally of official Israeli figures.

Militants also seized 250 hostages, and Israel says around 132 remain in Gaza. That number includes at least 28 dead hostages, according to an AFP tally based on Israeli figures.

Israel, in response, launched a relentless military offensive that the Palestinian territory's health ministry says has killed more than 26,000 people.

On Thursday, Tedros was moved to tears as he addressed the WHO's executive board. 

The fact that 70 percent of the fatalities in the Gaza Strip have been women and children should be motive enough to bring about a "long overdue" ceasefire, he said.

"If we look for a solution it's always possible," he added, after pausing to compose himself. "It's only the will that's required."

Tedros occasionally becomes emotional when speaking about the impact of war on children, citing his own early years in Ethiopia.

"I am a true believer because of my own experience that war doesn't bring solutions except more war, more hatred, more agony, more destruction," he said Thursday, wiping his eyes.

"I'm struggling to speak because... the situation is beyond words."